<template>
  <div
      id="editor"
      class="editor"
      :class="{ edit: isEdit }"
        :style="{
        ...getCanvasStyle(canvasStyleData),
        width: changeStyleWithScale(canvasStyleData.width) + 'px',
        height: changeStyleWithScale(canvasStyleData.height) + 'px',
        }"
      @contextmenu="handleContextMenu"
      @mousedown="handleMouseDown"  >

    <Shape
        v-for="(item, index) in componentData"
        :key="item.id"
        :default-style="item.style"
        :style="getShapeStyle(item.style)"
        :active="item.id === (curComponent || {}).id"
        :element="item"
        :index="index"
        :class="{ lock: item.isLock }"
    >
      <component
          :is="item.component"
          v-if="item.component.startsWith('SVG')"
          :id="'component' + item.id"
          :style="getSVGStyle(item.style)"
          class="component"
          :prop-value="item.propValue"
          :element="item"
          :request="item.request"
          :obj="item"
      />
      <component
          :is="item.component"
          v-else-if="item.component != 'VText'"
          :id="'component' + item.id"
          class="component"
          :style="getComponentStyle(item.style)"
          :prop-value="item.propValue"
          :element="item"
          :request="item.request"
          :obj="item"
      />

      <component
          :is="item.component"
          v-else
          :id="'component' + item.id"
          class="component"
          :style="getComponentStyle(item.style)"
          :prop-value="item.propValue"
          :element="item"
          :request="item.request"
          @input="handleInput"
          :obj="item"
      />
    </Shape>

    <!-- 右击菜单 -->
    <ContextMenu />
    <!-- 标线 -->
<!--    <MarkLine />-->

    <!-- 选中区域 -->
    <Area
        v-show="isShowArea"
        :start="start"
        :width="width"
        :height="height"
    />

  </div>`
</template>

<script>
// @ is an alias to /src

import { mapState } from 'vuex'
import Shape from './Shape'
import { getStyle, getComponentRotatedStyle, getShapeStyle, getSVGStyle, getCanvasStyle } from '@/utils/style'
import { $, isPreventDrop } from '@/utils/utils'
import eventBus from '@/utils/eventBus'
import { changeStyleWithScale } from '@/utils/translate'
import Area from "@/components/Editor/Area";

import ContextMenu from './ContextMenu'
// import MarkLine from './MarkLine'
// import Area from './Area'
// import Grid from './Grid'

export default {
  name: "DrawCanvas",
  // components: { Shape, ContextMenu, MarkLine, Area, Grid },
  components: { Shape, Area, ContextMenu },
  props: {
    isEdit: {
      type: Boolean,
      default: true,
    },
  },
  data() {
    return {
      editorX: 0,
      editorY: 0,
      start: { // 选中区域的起点
        x: 0,
        y: 0,
      },
      width: 0,
      height: 0,
      isShowArea: false,
      svgFilterAttrs: ['width', 'height', 'top', 'left', 'rotate'],
    }
  },
  computed: mapState([
    'componentData',
    'curComponent',
    'canvasStyleData',
    'editor',
  ]),
  mounted() {
    // 获取编辑器元素
    this.$store.commit('getEditor')

    eventBus.$on('hideArea', () => {
      this.hideArea()
    })

    // console.log(this.getCanvasStyle(this.canvasStyleData))
  },
  methods: {
    getShapeStyle,
    getCanvasStyle,
    changeStyleWithScale,

    handleMouseDown(e) {
      // 如果没有选中组件 在画布上点击时需要调用 e.preventDefault() 防止触发 drop 事件
      if (!this.curComponent || (isPreventDrop(this.curComponent.component))) {
        e.preventDefault()
      }

      this.hideArea()

      // 获取编辑器的位移信息，每次点击时都需要获取一次。主要是为了方便开发时调试用。
      const rectInfo = this.editor.getBoundingClientRect()
      this.editorX = rectInfo.x
      this.editorY = rectInfo.y

      const startX = e.clientX
      const startY = e.clientY
      this.start.x = startX - this.editorX
      this.start.y = startY - this.editorY
      // 展示选中区域
      this.isShowArea = true

      const move = (moveEvent) => {
        this.width = Math.abs(moveEvent.clientX - startX)
        this.height = Math.abs(moveEvent.clientY - startY)
        if (moveEvent.clientX < startX) {
          this.start.x = moveEvent.clientX - this.editorX
        }

        if (moveEvent.clientY < startY) {
          this.start.y = moveEvent.clientY - this.editorY
        }
      }

      const up = (e) => {
        document.removeEventListener('mousemove', move)
        document.removeEventListener('mouseup', up)

        if (e.clientX == startX && e.clientY == startY) {
          this.hideArea()
          return
        }

        this.createGroup()
      }

      document.addEventListener('mousemove', move)
      document.addEventListener('mouseup', up)
    },

    hideArea() {
      this.isShowArea = 0
      this.width = 0
      this.height = 0

      this.$store.commit('setAreaData', {
        style: {
          left: 0,
          top: 0,
          width: 0,
          height: 0,
        },
        components: [],
      })
    },

    createGroup() {
      // 获取选中区域的组件数据
      const areaData = this.getSelectArea()
      if (areaData.length <= 1) {
        this.hideArea()
        return
      }

      // 根据选中区域和区域中每个组件的位移信息来创建 Group 组件
      // 要遍历选择区域的每个组件，获取它们的 left top right bottom 信息来进行比较
      let top = Infinity, left = Infinity
      let right = -Infinity, bottom = -Infinity
      areaData.forEach(component => {
        let style = {}
        if (component.component == 'Group') {
          component.propValue.forEach(item => {
            const rectInfo = $(`#component${item.id}`).getBoundingClientRect()
            style.left = rectInfo.left - this.editorX
            style.top = rectInfo.top - this.editorY
            style.right = rectInfo.right - this.editorX
            style.bottom = rectInfo.bottom - this.editorY

            if (style.left < left) left = style.left
            if (style.top < top) top = style.top
            if (style.right > right) right = style.right
            if (style.bottom > bottom) bottom = style.bottom
          })
        } else {
          style = getComponentRotatedStyle(component.style)
        }

        if (style.left < left) left = style.left
        if (style.top < top) top = style.top
        if (style.right > right) right = style.right
        if (style.bottom > bottom) bottom = style.bottom
      })

      this.start.x = left
      this.start.y = top
      this.width = right - left
      this.height = bottom - top

      // 设置选中区域位移大小信息和区域内的组件数据
      this.$store.commit('setAreaData', {
        style: {
          left,
          top,
          width: this.width,
          height: this.height,
        },
        components: areaData,
      })
    },

    getSelectArea() {
      const result = []
      // 区域起点坐标
      const { x, y } = this.start
      // 计算所有的组件数据，判断是否在选中区域内
      this.componentData.forEach(component => {
        if (component.isLock) return

        const { left, top, width, height } = getComponentRotatedStyle(component.style)
        if (x <= left && y <= top && (left + width <= x + this.width) && (top + height <= y + this.height)) {
          result.push(component)
        }
      })

      // 返回在选中区域内的所有组件
      return result
    },

    handleContextMenu(e) {
      this.$store.commit( "setSelectShapeIndex", -1 )   //取消选择

      e.stopPropagation()
      e.preventDefault()

      // 计算菜单相对于编辑器的位移
      let target = e.target
      let top = e.offsetY
      let left = e.offsetX
      while (target instanceof SVGElement) {
        target = target.parentNode
      }

      while (!target.className.includes('editor')) {
        left += target.offsetLeft
        top += target.offsetTop
        target = target.parentNode
        console.log('right click')
      }

      this.$store.commit('showContextMenu', { top, left })
    },

    getComponentStyle(style) {
      return getStyle(style, this.svgFilterAttrs)
    },

    getSVGStyle(style) {
      return getSVGStyle(style, this.svgFilterAttrs)
    },

    handleInput(element, value) {
      // 根据文本组件高度调整 shape 高度
      this.$store.commit('setShapeStyle', { height: this.getTextareaHeight(element, value) })
    },

    getTextareaHeight(element, text) {
      if( !element.style )
        return  1.5
      let { lineHeight, fontSize, height } = element.style
      if (lineHeight === '') {
        lineHeight = 1.5
      }

      const newHeight = (text.split('<br>').length - 1) * lineHeight * (fontSize || this.canvasStyleData.fontSize)
      return height > newHeight ? height : newHeight
    },
  },
}
</script>

<style lang="scss" scoped>
.editor {
  position: relative;
  background: #fff;
  margin: auto;

  .lock {
    opacity: .5;

    &:hover {
      cursor: not-allowed;
    }
  }
}

.edit {
  .component {
    outline: none;
    width: 100%;
    height: 100%;
  }
}
</style>

<!--export default {-->
<!--  name: 'DrawCanvas',-->
<!--  components: {-->

<!--  }-->
<!--}-->
<!--</script>-->
